I mean in the "real world" what happens is you do this once, and then you keep on using it and gradually make changes. Annoying, of course, but I think cargo is

I mean in the "real world" what happens is you do this once, and then you keep on using it and gradually make changes. Annoying, of course, but I think cargo is fortunately still relatively simple stuff, so the scope is much smaller than, say, Python setup.py shenanigans (though Rust build.rs stuff will definitely require some futzing around with environment variables at the Cargo level). The "obvious" thing would be to either generate cargo files from Bazel stuff, generate Bazel stuff from cargo files, or have a third source that generates both. And like... yeah, if you are suffering from compile time issues, Bazel can make that stuff order of magnitudes faster (especially if your dep tree is pretty horizontal), so there's a reason to do it!